摘 要: 针对非同分布的Nakagami信道,基于矩生成函数MGF(Moment Generation Function)的分析方法,提出正交空时分组码系统STBC(Space-Time Block Coding)的一种快速性能评估算法,不需要涉及超几何函数积分运算,可在中高信噪比时,快速准确地估计STBC系统的符号错误概率性能。在平坦瑞利衰落信道下的计算机仿真表明,该算法与已有的STBC系统的近似估计算法相比,具有较优的性能。 关键词: 正交空时分组码; MIMO; MGF; 误符号率
上传时间: 2014-12-29
上传用户:如果你也听说
The field of microelectromechanical systems (MEMS), particularly micromachinedmechanical transducers, has been expanding over recent years, and the productioncosts of these devices continue to fall. Using materials, fabrication processes, anddesign tools originally developed for the microelectronic circuits industry, newtypes of microengineered device are evolving all the time—many offering numerousadvantages over their traditional counterparts. The electrical properties of siliconhave been well understood for many years, but it is the mechanical properties thathave been exploited in many examples of MEMS. This book may seem slightlyunusual in that it has four editors. However, since we all work together in this fieldwithin the School of Electronics and Computer Science at the University of Southampton,it seemed natural to work together on a project like this. MEMS are nowappearing as part of the syllabus for both undergraduate and postgraduate coursesat many universities, and we hope that this book will complement the teaching thatis taking place in this area.
上传时间: 2013-10-16
上传用户:朗朗乾坤
机电类比法是一种把机械量通过一定的计算等效类比为电量的方法,其在对电子机械系统的分析中应用非常广泛。它能够把一个较复杂的机械系统类比为我们熟知的电路系统来进行分析,从而使问题的分析得到简化。本文通过对振弦式传感器的分析介绍了机电类比法,并对使用电路进行了相关的分析。 Summary:The electromechanical analogy is assort of analysis which is to analogize the mechanical system by using circuit system , it applied widely in the filed of analysis the electronic-mechanical system. The analysis can take a complex mechanical system analogous to a circuitry that we well-known, which can simplify the problems. In the paper, the electro-mechanical analogy method is briefly introduced by analysis the vibrating wire sensor,and have a correlation analysis about the circuit we used.关键词: 机电类比法 振弦式传感器 频率 振荡 反馈Keyword:electro-mechanical analogy method,vibrating wire sensor,frequency, oscillation, feedback 0 引言振弦式传感器是属于频率式传感器的一种。所谓频率式传感器就是能直接将被测量转换为振动频率信号的传感器,这类传感器一般是通过测量振弦、振筒、振梁、振膜等弹性振体或石英晶体谐振器的固有谐振频率来达到测量引起谐振频率变化的被测非电量的目的,其也称为谐振式传感器[1]。在分析该类传感器中,由于其涉及到频率,就容易让人联想到在电子技术中接触到的RLC振荡电路。因此可以尝试着用类比的方法使之对应起来分析,即机电类比法分析。
上传时间: 2013-11-16
上传用户:paladin
User ManualRev. 1.2SmartRF® CC2420DK: Packet Sniffer for IEEE 802.15.4 and ZigBee Table of contents1 INTRODUCTION...............................................................................................31.1 HARDWARE PLATFORM.......................................................................................31.2 SOFTWARE.........................................................................................................32 USER INTERFACE..........................................................................................42.1 MENUS AND TOOLBARS.......................................................................................62.2 SETUP................................................................................................................62.3 SELECT FIELDS...................................................................................................72.3.1 Tips............................................................................................................72.4 PACKET DETAILS.................................................................................................72.5 ADDRESS BOOK..................................................................................................92.5.1 Tips............................................................................................................92.6 DISPLAY FILTER................................................................................................102.7 TIME LINE.........................................................................................................103 HELP....................................................................................................................114 TROUBLESHOOTING..................................................................................125 GENERAL INFORMATION........................................................................135.1 DOCUMENT HISTORY........................................................................................135.2 DISCLAIMER......................................................................................................135.3 TRADEMARKS...................................................................................................136 ADDRESS INFORMATION........................................................................14
上传时间: 2014-01-14
上传用户:zhangyi99104144
A Computer-On-Module, or COM, is a Module with all components necessary for a bootable host computer, packaged as a super component. A COM requires a Carrier Board to bring out I/O and to power up. COMs are used to build single board computer solutions and offer OEMs fast time-to-market with reduced development cost. Like integrated circuits, they provide OEMs with significant freedom in meeting form-fit-function requirements. For all these reasons the COM methodology has gained much popularity with OEMs in the embedded industry. COM Express® is an open industry standard for Computer-On-Modules. It is designed to be future proof and to provide a smooth transition path from legacy parallel interfaces to LVDS (Low Voltage Differential Signaling) interfaces. These include the PCI bus and parallel ATA on the one hand and PCI Express and Serial ATA on the other hand.
上传时间: 2013-11-05
上传用户:Wwill
We all know the benefits of using FieldProgrammable Gate Arrays (FPGAs): no NRE, nominimum order quantities, and faster time-tomarket.In an ideal world, designs would never needto be changed because of design errors, but we allknow that sometimes this is necessary.
上传时间: 2013-11-04
上传用户:leixinzhuo
The use of the Wind River VxWorks Real-Time Operating System (RTOS) on Virtex™-4embedded PowerPC™ processors continues to be a popular choice for high performanceFPGA designs. The introduction of the Wind River Workbench design environment has enableda new and easier way for designers to control the configuration of the VxWorks kernel. Thisguide shows the steps required to build and configure a ML403 Embedded DevelopmentPlatform to boot and run the VxWorks RTOS. A VxWorks bootloader is created, programmedinto Flash, and used to boot the design. The concepts presented here can be scaled to anyPowerPC enabled development platform.
上传时间: 2013-10-26
上传用户:agent
The NCV7356 is a physical layer device for a single wire data linkcapable of operating with various Carrier Sense Multiple Accesswith Collision Resolution (CSMA/CR) protocols such as the BoschController Area Network (CAN) version 2.0. This serial data linknetwork is intended for use in applications where high data rate is notrequired and a lower data rate can achieve cost reductions in both thephysical media components and in the microprocessor and/ordedicated logic devices which use the network.The network shall be able to operate in either the normal data ratemode or a high-speed data download mode for assembly line andservice data transfer operations. The high-speed mode is onlyintended to be operational when the bus is attached to an off-boardservice node. This node shall provide temporary bus electrical loadswhich facilitate higher speed operation. Such temporary loads shouldbe removed when not performing download operations.The bit rate for normal communications is typically 33 kbit/s, forhigh-speed transmissions like described above a typical bit rate of83 kbit/s is recommended. The NCV7356 features undervoltagelockout, timeout for faulty blocked input signals, output blankingtime in case of bus ringing and a very low sleep mode current.
上传时间: 2013-10-24
上传用户:s蓝莓汁
With the Altera Nios II embedded processor, you as the system designercan accelerate time-critical software algorithms by adding custominstructions to the Nios II processor instruction set. Using custominstructions, you can reduce a complex sequence of standard instructionsto a single instruction implemented in hardware. You can use this featurefor a variety of applications, for example, to optimize software innerloops for digital signal processing (DSP), packet header processing, andcomputation-intensive applications. The Nios II configuration wizard,part of the Quartus® II software’s SOPC Builder, provides a graphicaluser interface (GUI) used to add up to 256 custom instructions to theNios II processor
上传时间: 2013-11-07
上传用户:swing
The CC1101 is a low-cost sub- 1 GHztransceiver designed for very low-powerwireless applications. The circuit is mainlyintended for the ISM (Industrial, Scientific andMedical) and SRD (Short Range Device)frequency bands at 315, 433, 868, and 915MHz, but can easily be programmed foroperation at other frequencies in the 300-348MHz, 387-464 MHz and 779-928 MHz bands.CC1101 is an improved and code compatibleversion of the CC1100 RF transceiver. Themain improvements on the CC1101 include:
上传时间: 2013-11-12
上传用户:363186